[fpc-devel] Addtions for strutils

[ik]

On 1/21/06, Marco van de Voort <marcov at stack.nl> wrote:
> > I wish to add 3 new string functions for strutils:
> > 1. Check if a string is an integer (without + or - signs).
>
> Hmm, is this not a bit overspecialisation ?
>
> val(x,code);
> result:=(code=0)  and (posexset(['+','-'],x)=0)
>
> would already do. (untested from memory)
>

And why is that better ? I do a loop and see if I only have the valid
chars or stop. What happen if I have a number with 20 or 50 chars
based ? I only want to check if it contains a valid number chars, not
to actually convert it to anything (no one promise you that you can
convert it to any existed type!).

> > 2. split a string into an array using a giving separator.
>
> In some form already exists. (e.g. tstringlist) however that has some
> limitations.

I also did a TString based function that does the same (a long time
ago.. my code is based on an old Delphi and TP unit I written), but as
you said TString (descendant) also have it ...

>
> However so has yours:
> - separator aggregates are not supported.

Well it was made to be separated with one char, but you can add
support to a string or a charset if you really want :)


> - there is too much copy() ing going on.
I'm still looking for a way to know if a char exists even if the
string is empty without any "Access Violation" errors... copy is the
best hack I can think about, alto I thought today on a better way to
do it ... maybe I'll rewrite it ...

> I do agree however that such function, without tstringlists limitations is
> needed, but we need something more general I think.

Can you tell me what exactly is needed ? I changed this functions from
an old unit I made (as I written above), and I'm using it in my IP
Calc unit (that I'm still writing).
One of the reasons I wish to see it appear on FPC is because some
people actually interested in this unit, and thous people are not
using FPC at all, so it can be a good place to start.

Ido